Obs. : 2014-01-13 Planet Ly alpha (photons/cm^2/sec) Mercury 4.027e+11 Venus 3.993e+11 Earth 4.054e+11 Mars 4.423e+11 Jupiter 4.136e+11 Saturn 4.171e+11 Uranus 3.905e+11 Neptune 4.019e+11 Pluto 3.993e+11